In-line pegged hybrid glenoid

ABSTRACT

A glenoid implant can include a body, a first fixation member, a second fixation member, and a third fixation member. The body can include an articular surface and a scapula-engaging surface opposite from the articular surface. The first, second and third fixation members can extend from the scapula-engaging surface. The third fixation member can include a porous titanium material and be disposed between the first and second fixation members, such that the first, second and third fixation members define a substantially linear configuration.

FIELD

The present disclosure relates to an implant, and more particularly to adevice and method for securing a glenoid implant to a glenoid, includinga glenoid having a narrow, or otherwise small, geometry.

BACKGROUND

This section provides background information related to the presentdisclosure and is not necessarily prior art.

Surgical procedures for repairing or reconstructing a joint may requiresecurely fastening a surgical implant to a bone. For example, shoulderjoint reconstruction may require fixing a glenoid implant to a scapulato reproduce or replicate a glenoid cavity on the scapula. In somesituations, the glenoid cavity may present a narrow or otherwise smallsurface area, or other geometry, on which to secure the glenoid implant.The glenoid implant may include pegs distributed in a variety ofconfigurations around the periphery of the implant. Corresponding holesmay be formed in the scapula for receiving the pegs. In someconfigurations, the pegs may be received within the holes in a press-fitconfiguration. In addition, bone cement may be used to secure the pegswithin the holes.

While known surgical implants have proven to be acceptable for theirintended purposes, a continuous need for improvement in the relevant artremains.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to one particular aspect, the present disclosure provides aglenoid implant. The glenoid implant can include a body, a firstfixation member, a second fixation member, and a third fixation member.The body can include an articular surface and a scapula-engaging surfaceopposite from the articular surface. The first, second and thirdfixation members can extend from the scapula-engaging surface. The thirdfixation member can include a porous titanium material and be disposedbetween the first and second fixation members, such that the first,second and third fixation members define a substantially linearconfiguration.

According to another particular aspect, the present disclosure providesan implant. The implant can include a body, a first fixation member anda second fixation member. The body can include an articular surface anda scapula-engaging surface opposite from the articular surface. The bodycan be at least partially formed from a first biocompatible material.The first and second fixation members can extend from a central portionof the scapula-engaging surface such that the first and second fixationmembers define an axis of symmetry relative to the scapula-engagingsurface. At least one of the first and second fixation members can beformed from a second biocompatible material that is different than thefirst biocompatible material.

According to yet another particular aspect, the present disclosureprovides a glenoid implant. The glenoid implant can include a body afirst fixation member, a second fixation member, and a third fixationmember. The body can include an articular surface and a scapula-engagingsurface opposite from the articular surface. The body can be at leastpartially formed from a first biocompatible material. The first, secondand third fixation member can extend from the scapula-engaging surfaceand be disposed in a central portion of the glenoid implant. The thirdfixation member can include a second biocompatible material differentthan the first biocompatible material.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a first perspective view of a glenoid implant in accordancewith the principles of the present disclosure;

FIG. 2 is a second perspective view of the glenoid implant of FIG. 1;

FIG. 3 is a side view of the glenoid implant of FIG. 1;

FIG. 4 is a top view of the glenoid implant of FIG. 1; and

FIG. 5 is a front view of the glenoid implant of FIG. 1.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

With general reference to FIGS. 1-5 of the drawings, an implantconstructed in accordance with the principles of the present disclosureis illustrated and identified at reference character 10. According toone exemplary use, the implant 10 may be a glenoid implant for use inshoulder joint replacement. In such case, the glenoid implant canreplace or replicate an entire glenoid cavity or a portion thereof foranatomic shoulder joint replacements. The glenoid implant can also filla defect in the glenoid cavity such as a void due to severe wear. Itwill also be appreciated, however, that the present teachings may beadapted to fix various implants to various bones.

The implant 10 may generally include a body 12. The body 12 may be agenerally rectangular body 12 having a pear-shaped outline (by way ofnon-limiting example), a central fixation member 14, and a pair ofperipheral fixation members 16. The implant 10 can be formed from anybiocompatible material, including, polymer, ceramic, metal orcombinations thereof. In some configurations, the body 12 and/or theperipheral fixation members 16 may be formed from a polyethylenematerial such as an ultrahigh molecular weight polyethylene or a highlycross-linked polyethylene. The body 12 and/or the peripheral fixationmembers 16 may also include, via doping, blending, infusion or anothersuitable process for combining materials, an antioxidant, such as E1®,commercially available from Biomet Manufacturing Corporation®, forexample.

The implant 10, including at least the body 12 and the peripheralfixation members 16, can be formed using any suitable manufacturingtechnique, including machining, direct compression molding and/oradditive manufacturing which enables forming multiple implants in asingle build and decreases manufacturing time. Once formed, the implant10 can be further processed (e.g., polished, blasted, machining) asdesired. For example, the implant 10 can be polished for articulationwith a humeral head made from polyethylene or another suitable material.Alternatively, polyethylene can be molded over or pressed onto the body12 for articulation with a metal humeral head.

The body 12 may be substantially similar to the “body 12” shown anddescribed in commonly-owned U.S. patent application Ser. No. 14/095,565filed Dec. 3, 2013 and entitled “Patient-Specific Glenoid Implant”,which is hereby incorporated by reference in its entirety. In thisregard, the body 12 extends along a central longitudinal axis A (FIG. 5)and has a peripheral surface 18, an articular surface 20, and ascapula-engaging surface 22 opposite from the articular surface 20. Theperipheral surface 18 includes superior and infererior portions 18 a, 18b that are rounded (e.g., concave), and anterior and posterior portions18 c, 18 d that are flat or slightly rounded (e.g., convex). Theperipheral surface 18 can be patient-specific and can match or replicatea peripheral surface of a glenoid cavity of a specific patient. Thecentral fixation member 14 and the peripheral fixation members 16 extendfrom the scapula-engaging surface 22 of the body 12. In this regard, thecentral fixation member 14 may extend from the scapula-engaging surface22 along a first central axis A1, while the peripheral fixation members16 may extend from the scapula-engaging surface 22 along second andthird central axes A2, A3, respectively. Although the implant 10 isshown with two peripheral fixation members 16, the implant 10 caninclude additional or fewer peripheral fixation members 16.

The articular surface 20 is configured to partially receive andnestingly engage or articulate with the humeral head. For example, thearticular surface 20 can be patient-specific and can have a concavehemispherical shape that closely conforms as mirror-image or negative ora complementary surface of the humeral head. The humeral head can bepart of a natural humerus of a specific patient, or the humeral head canbe part of a humeral implant. A 3D model of the humeral head can beobtained using an x-ray, MRI, CT, ultrasound or other medical scan, andthe articular surface 20 can be designed (e.g., shaped, sized,contoured) based on the 3D model. If the humeral head is part of ahumeral implant, the 3D model can be obtained from the CAD files used todesign the humeral implant.

The scapula-engaging surface 22 may include a plurality of protrusionsor teeth 23 extending therefrom. The teeth 23 may be shaped as pyramidalfrustums, for example. In one configuration, the teeth 23 may be shapedas truncated square pyramids. The teeth 23 may be arranged in a grid orarray of orthogonally disposed rows, helping bone cement to flow orotherwise disburse between the bone and the bone-engaging side.

The central fixation member 14 and/or the peripheral fixation members 16can be formed integral with the body 12 or separate from the body 12. Inone example, the peripheral fixation members 16 can be formed integralwith the body 12, and the central fixation member 14 can be formedseparate from the body 12 and press fit or threaded into a blind hole inthe body 12. The blind hole can be formed in a domed portion 24 (FIG. 3)of the body 12 that extends from the scapula-engaging surface 22. Inthis regard, the implant 10 can also include an internally-threadedinsert 25 that is disposed, and otherwise secured within (e.g.,press-fit, adhesive, mechanical fasteners, etc.) the blind hole. Theinsert 25 can be formed from a metallic, or other similar high strengthmaterial, thus helping to ensure that the central fixation member 14 issecurely coupled to the insert 25 and the body 12. The central fixationmember 14 may be formed from a biocompatible material, such as a porousmetallic material. For example, in some configurations, the centralfixation member 14 may include, or otherwise be formed from, a poroustitanium material such as REGENEREX®, or OSSEOTI®, both of which arecommercially available from Biomet Manufacturing Corporation. The porousmetal material of the central fixation member 14 can allow for theingrowth of bone into the central fixation member 14, thereby improvingthe fixation of the central fixation member 14 and the implant 10relative to the glenoid or other bone.

The central fixation member 14 may be substantially similar to the“central peg 14” found in commonly owned U.S. patent application Ser.No. 14/095,565. In this regard, the central fixation member 14 includesa first portion 26, a second portion 28 that extends from the firstportion 26, a third portion 30 that extends from the second portion 28,and a fourth portion 32 that extends from the third portion 30. Thefirst, second, and third portions 26, 28, and 30 can be cylindrical andconcentric, and the fourth portion 32 can be a rectangular cube oranother non-cylindrical shape for receipt in a drive tool such as asocket. In this regard, it will be appreciated that while the fourthportion 32 is illustrated and described as extending from the thirdportion 30, the fourth portion 32 may alternatively include a divot orrecessed portion (not shown) formed in the fourth portion 32. The divotor recessed portion may similarly define a cubic, hexagonal, ornon-cylindrically shaped void for receipt of a drive tool such as ascrewdriver or Allen wrench. As shown in FIG. 3, the first portion 26can have a first diameter D1, the second portion 28 can have a seconddiameter D2 that is less than the first diameter D1, and the thirdportion 30 can have a third diameter D3 that is less than the seconddiameter D2. Thus, the central fixation member 14 can decrease indiameter from the first portion 26 to the third portion 30 in a steppedmanner, which may strengthen a press fit between the central fixationmember 14 and a corresponding hole in the scapula. Alternatively, thediameter of the central fixation member 14 can be decreased in a taperedmanner to strengthen the press fit.

The central fixation member 14 may be located at a central portion orregion of the scapula-engaging surface 22, relative to the superior andinferior portions 18 a, 18 b, and/or relative to the anterior andposterior portions 18 c, 18 d, of the peripheral surface 18. In thisregard, as illustrated in FIG. 5, in some configurations a firstlaterally extending distance X1 between the central fixation member 14and a first location 34 on the peripheral surface 18 may besubstantially equal to a second laterally extending distance X2 betweenthe central fixation member 14 and a second location 36 on theperipheral surface 18. The first location 34 may be aligned with thesecond location 36 relative to the longitudinal axis A of the body 12,such that a line extending from the first location 34 to the secondlocation 36 intersects the first central axis A1. In this regard, insome configurations the distance X1 may extend from the anterior portion18 c to the first central axis A1, and the distance X2 may extend fromthe posterior portion 18 d to the first central axis A1.

With continued reference to FIG. 5, the peripheral fixation members 16may be located at a central portion or region of the scapula-engagingsurface 22, relative to the anterior and posterior portions 18 c, 18 dof the peripheral surface 18. In this regard, in some configurations, athird distance X3 between the superior peripheral fixation member 16 anda third location 38 on the peripheral surface 18 may be substantiallyequal to a fourth distance X4 between the superior peripheral fixationmember 16 and a fourth location 40 on the peripheral surface 18. Thethird location 38 may be aligned with the fourth location 40 relative tothe longitudinal axis A of the body 12, such that a line extending fromthe third location 38 to the fourth location 40 intersects the secondcentral axis A2. In this regard, in some configurations the thirddistance X3 may extend from the anterior portion 18 c to the secondcentral axis A2, and the fourth distance X4 may extend from theposterior portion 18 d to the second central axis A2. Similarly, in someconfigurations, a fifth distance X5 between the inferior peripheralfixation member 16 and a fifth location 42 on the peripheral surface 18may be substantially equal to a sixth distance X6 between the inferiorperipheral fixation member 16 and a sixth location 44 on the peripheralsurface 18. The fifth location 42 may be aligned with the sixth location44 relative to the longitudinal axis A of the body 12, such that a lineextending from the fifth location 42 to the sixth location 44 intersectsthe third central axis A3. In this regard, in some configurations thefifth distance X5 may extend from the inferior portion 18 b to the thirdcentral axis A3, and the sixth distance X6 may extend from the inferiorportion 18 b to the third central axis A3.

The central fixation member 14 may be disposed between the peripheralfixation members 16 such that the superior peripheral fixation member 16may be located a seventh distance Y7 from the central fixation member14, and the inferior peripheral fixation member 16 may be located aneighth distance Y8 from the central fixation member 14. In this regard,the seventh distance Y7 may extend from and between the first and secondcentral axes A1, A2, and the eighth distance Y8 may extend from andbetween the first and third central axes A1, A3. In some configurations,the seventh distance Y7 may be substantially equal to the eighthdistance Y8. It will be appreciated, however, that the seventh distanceY7 may differ from the eighth distance Y8 within the scope of thepresent disclosure.

At least two of the central fixation member 14 and the peripheralfixation members 16 may be centrally located relative to the anteriorand posterior portions 18 c, 18 d of the peripheral surface 18, suchthat the central longitudinal axis A intersects the central fixationmember 14 and/or the peripheral fixation member(s) 16. As illustrated inFIG. 5, in some configurations, the central fixation member 14 may bedisposed between the peripheral fixation members 16, such that thecentral fixation member 14 and the peripheral fixation members 16 definea substantially linear configuration along the central longitudinal axisA. As illustrated, the central longitudinal axis A may define an axis ofsymmetry of the scapula-engaging surface 22 and/or the implant 10.

It will be appreciated that the centrally located, linear configurationof the central fixation member 14 and/or the peripheral fixation members16 can allow for the improved placement of the implant 10 in a glenoidhaving a narrow or otherwise small surface area. In this regard, theimplant 10 is configured to be fixed to a scapula without using fixationhardware such as bone screws. For example, the central fixation member14 and the peripheral fixation members 16 can be press fit into holesformed in a central portion of the glenoid cavity to fix the implant tothe scapula. As discussed above, the porous construct of the materialforming the central fixation member 14 can allow for the ingrowth ofbone into the central fixation member 14, further improving the fixationof the central fixation member 14 and the implant 10 relative to theglenoid or other bone. In addition, annular grooves 46, defining fins orflanged portions 48, can be formed in the peripheral fixation members 16for receiving bone cement to fix the peripheral fixation members 16within corresponding holes in the scapula. In this regard, in someconfigurations the peripheral fixation members 16 may include an annularfin (not shown) substantially similar to the “annular fin 40” found incommonly owned U.S. patent application Ser. No. 14/226,051 filed Mar.26, 2014 and entitled “Press-Fit Glenoid with Peripheral CompressionPegs”, which is hereby incorporated by reference in its entirety.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

1. (canceled)
 2. A glenoid implant comprising: a body having anarticular surface and a scapula-engaging surface opposite from thearticular surface, the scapula-engaging surface including a plurality ofteeth extending therefrom; an insert secured within a blind hole locatedin the body, the insert secured by mechanical fasteners or an adhesive;a first fixation member extending from the scapula-engaging surface; asecond fixation member extending from the scapula-engaging surface; anda third fixation member configured to extend from the scapula-engagingsurface and threadably connect to the insert, the third fixation memberincluding a porous titanium material and being disposed between thefirst and second fixation members, such that the first, second and thirdfixation members define a substantially linear configuration.
 3. Theglenoid implant of claim 2, wherein the substantially linearconfiguration defines a central axis relative to the scapula-engagingsurface.
 4. The glenoid implant of claim 2, wherein the third fixationmember is removably coupled to the implant.
 5. The glenoid implant ofclaim 2, wherein the third fixation member includes a stepped outersurface including a first portion, a second portion, a third portion,and a fourth portion, the first portion, the second portion, and thethird portion each being cylindrical and having a diameter that differsfrom one another, the fourth portion having a non-cylindrical shapesized to receive a drive tool, the first portion, the second portion,the third portion, and the fourth portion being a different materialthan the body.
 6. The glenoid implant of claim 2, wherein the first andsecond fixation members include a radially extending flange.
 7. Theglenoid implant of claim 2, wherein the body includes a polyethylenematerial.
 8. The glenoid implant of claim 2, wherein at least one of thefirst and second fixation members includes the polyethylene material. 9.The glenoid implant of claim 2, wherein the polyethylene materialincludes an antioxidant.
 10. The glenoid implant of claim 2, wherein thescapula-engaging surface mirrors and conforms to a surface of a glenoidcavity of a patient.
 11. An implant comprising: a body having anarticular surface and a scapula engaging surface opposite from thearticular surface, the body being at least partially formed from a firstbiocompatible material, the scapula-engaging surface including aplurality of teeth extending therefrom and arranged in a grid; an insertsecured within a blind hole located in the body at a central portion ofthe scapula engaging surface, the insert secured by mechanical fastenersor an adhesive; first and second fixation members extending from thecentral portion of the scapula-engaging surface, such that the first andsecond fixation members define an axis of symmetry relative to thescapula-engaging surface, at least one of the first and second fixationmembers includes a second biocompatible material that is different thanthe first biocompatible material; and a third fixation member configuredto extend from and threadably connect to the insert, the second fixationmember being disposed between the first and third fixation members, suchthat the first, second and third fixation members define a substantiallylinear configuration.
 12. The glenoid implant of claim 11, wherein thesecond biocompatible material includes a porous titanium material. 13.The glenoid implant of claim 11, wherein the first biocompatiblematerial includes a polyethylene material.
 14. The glenoid implant ofclaim 11, wherein the second fixation member is removably coupled to theimplant.
 15. The glenoid implant of claim 11, wherein the secondfixation member includes a porous titanium material.
 16. The glenoidimplant of claim 11, wherein the scapula-engaging surface mirrors andconforms to a surface of a glenoid cavity of a patient.
 17. A glenoidimplant, comprising: a body having an articular surface and ascapula-engaging surface opposite from the articular surface, the bodyat least partially formed from a first biocompatible material, thescapula-engaging surface including a plurality of teeth extendingtherefrom and arranged in an array of orthogonally disposed rows; aninsert secured within a blind hole located in body, the insert securedby mechanical fasteners or an adhesive; a first fixation memberextending from the scapula-engaging surface; a second fixation memberextending from the scapula-engaging surface; and a third fixation memberconfigured to extend from and threadably connect to the insert, thethird fixation member including a second biocompatible materialdifferent than the first biocompatible material, the first, second andthird fixation members being disposed in a central portion of theglenoid implant, wherein the third fixation member is disposed betweenthe first and second fixation members, such that the first, second andthird fixation members define a substantially linear configuration. 18.The glenoid implant of claim 17, wherein the second biocompatiblematerial includes a porous titanium material.
 19. The glenoid implant ofclaim 17, wherein the third fixation member is removably coupled to theglenoid implant.
 20. The glenoid implant of claim 17, wherein the thirdfixation member includes a stepped outer surface including a firstportion, a second portion, a third portion, and a fourth portion, thefirst portion, the second portion, and the third portion each beingcylindrical and having a diameter that differs from one another, thefirst portion connected to the second portion by a first curved portion,the second portion connected to the third portion by a second curvedportion.
 21. The glenoid implant of claim 17, wherein the third fixationmember includes a stepped outer surface including a first portion, asecond portion, a third portion, and a fourth portion, the firstportion, the second portion, and the third portion each beingcylindrical and having a diameter that differs from one another, thefirst portion connected to the second portion by a first taperedportion, the second portion connected to the third portion by a secondtapered portion.